html,
body {
  height: 100%;
}

body {
  display: -ms-flexbox;
  display: -webkit-box;
  display: flex;
  -ms-flex-align: center;
  -ms-flex-pack: center;
  -webkit-box-align: center;
  align-items: center;
  -webkit-box-pack: center;
  justify-content: center;
  padding-top: 40px;
  padding-bottom: 40px;
  /*background-color: #f5f5f5;*/
  background-image: linear-gradient(-225deg, #69d2cb 0%, #c8c8f8 48%, #6654c8 100%);
}

.form-signin {
  width: 100%;
  max-width: 330px;
  padding: 20px;
  margin: 0 auto;
}
.form-signin .checkbox {
  font-weight: 400;
}
.form-signin .form-control {
  position: relative;
  box-sizing: border-box;
  height: auto;
  padding: 10px;
  font-size: 16px;
  margin-bottom: 5px;
  border-radius: 5px;
}
.form-signin .form-control:focus {
  z-index: 2;
}
.form-signin input[type="email"] {
  margin-bottom: -1px;
  border-bottom-right-radius: 0;
  border-bottom-left-radius: 0;
}
#bt0,#bt1,#bt2 {
  text-align: center;
  cursor: pointer; /* 将鼠标光标设为手型，表示可点击 */
  transition: box-shadow 0.3s ease; /* 添加过渡效果，使阴影变化平滑 */
}
#bt:hover {
  box-shadow: 0 0 10px 5px rgba(0, 123, 255, 0.5); /* 点击时显示阴影效果 */
}
#bt:active {
  box-shadow: 0 0 10px 5px rgba(0, 123, 255, 1); /* 点击时显示阴影效果 */
}
#bt:after {
  box-shadow: 0 0 10px 5px rgba(0, 123, 255, 0.75); /* 点击时显示阴影效果 */
}
